144 GHz epsilon-near-zero lens antenna

Metamaterials have revolutionized the design of lenses. Free-space matching has been traditionally achieved by thick anti-reflective coatings. However, at millimeter-waves, simple anti-reflective coatings remain elusive. In this range, the impedance matching attainable with metamaterials can be a viable solution. This holds promise for enhancing the gain of highly directive lens antennas.